@DW I doubt HO will warranty it is now with the release of the 2018's 6 model years old. @Horton this is the first season of use with only about 10 sets on it in salt water , my old Iconn Sonic C-6 held up to over 10 seasons and no issues . My fins and inserts never corrode, so this was the first time I had seen corrosion on any component. Hence the reason for the surprise , I will continue to use the fresh water rinsing and hope it does not get worse. Thanks to you both.